text:
What does 'EST' at the end of a NOTAM's valid time mean?
In this NOTAM below, the valid time is "2006280446-2007312359EST".
EST does not appear in the FAA NOTAM contractions list.

I assumed this EST meant "Eastern Standard Time", but that conflicts with the information shown below in ForeFlight.
This is what ForeFlight shows for the same NOTAM:

What does this "EST" mean?

In your ForeFlight screenshot, look at the word directly before "CREATED" in each of the NOTAMS.

@RalphJ true, and getting an FAA-source is much easier to defend than a private software product's interpretation.

If the NOTAM duration is expected to return to service prior to the
End of Validity time, the time is expressed by using a date-time group
followed immediately by EST (estimate).  Any NOTAM that includes an
EST must be canceled or replaced before the NOTAM reaches its  End of
Validity time. If the NOTAM is not canceled or replaced, it will
expire at the end  of validity time regardless of EST.

Reference:
https://www.faa.gov/documentlibrary/media/order/notam.pdf#page=7

Welcome to aviation.SE! Please use the quote formatting for direct quotes from other sources; apart from being good practice it helps people who use screen readers and other tools.

#page=7 would allow you to link the specific page in the .PDF also. Ie. https://www.faa.gov/documentlibrary/media/order/notam.pdf#page=7

Estimated.
Oddly, this isn't stated explicitly in JO 7930.2, Notices to Airmen (NOTAM).


text:
Do aviation intercoms have a standardized compatibility with radio stacks?
I have been seeking an intercom unit for a Cessna 172N that has four seats but only two headset jacks, and I would like my rear passengers to be able to communicate without yelling.
Aviation intercoms have external radio transmit switches, but the airplane also has its own built-in radio transmit system.  How does the transmit function trigger in this type of system?  Do they send a certain audio signal frequency or tone to the COM stack that tells it to transmit?
Are most intercoms universally compatible with all com stacks if they use the same plug types?

Not a tone, this is a simple contact (switch). Related: How does the PTT button on the radio work? Also if you search PTT or "push to talk" on the site, you'll get 3 pages of related questions.

I was not suggesting to delete the post. I think there are different connectors and wiring, but there is one frequently used. Someone will confirm.

This is a good question - the comments above answer most of it, but here are some more details:
Short answer: yes, they are pretty much standardised. Any modern GA intercom will work with any modern GA radio.
Part of the job of the intercom is to tell the radio when to transmit, and to route the correct microphone signal through to it. This is almost always done using a single wire which signals "transmit now", and a pair of wires for the microphone signal from the headset corresponding to the PTT button that was pushed.
On more advanced integrated setups, the signals might be transmitted over a digital bus, but outside of fully integrated setups like the G1000 (and even then on some models), there are always ways to connect standard aircraft radios to the intercom.

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text:
Does anxiety increase the likelihood of developing motion sickness?
In general, does a person's anxiety or "fear of flying" have an effect on his likelihood of experiencing motion sickness during flight?
I am wondering if providing some ground education to first-time flyers would have a positive impact on their experience by reducing anxiety levels and, therefore, the chances of needing to use regurgitation collection devices.
Assume all other factors such as specific G-forces and accelerations experienced, temperatures, meals eaten, etc. are controlled or disregarded.

Related

You are confusing correlation and causation. A correlation means that two things have a linear statistical relationship, not that one leads to another. Causation is anxiety leads to motion sickness, correlation could mean either leads to another. Maybe people are anxious because they develop motion sickness, not the other way around.

@GdD ::Pssst:: click the edit button ;)

Hmm... Assuming that education would help seems also to assume that the fear is usually a rational fear rather than an irrational one. I'm not sure that this is a valid assumption. Most people I've known who had a fear of flying really had more a fear of enclosed spaces or heights (or both.)

@reirab for sure. Education is definitely not a cure-all, and it definitely would matter what the fear is based on coupled with what is being taught to mitigate that fear.

If anyone here is pursuing a Ph.D. in psychology, this sounds like an interesting idea for a thesis.

Also, the average stack user isn't one of those, "...but... But what if the wings run out of pixie dust!?" People.

It's different for everyone, but I'd expect stress/anxiety to be a contributing factor for many, which is an ultimately self-defeating cycle; if you "know" you're going to get sick, you'll be anxious about that, and that'll make you sick.
The trigger for me is inadequate ventilation. I'm fortunate enough to rarely get motion sickness, but when it does happen it's usually because I'm in a hot, still cabin without a good source of fresh air.

(I'm not an expert...) FYI, the phobia of being sick is emetophobia. Not related, FAA analyzed studies on motion sickness in 1976. For non physical causes (like vestibular disorders) the idea commonly proposed is that phobias (which are very common), by creating anxiety which releases hormones like adrenalin or cortisol, are often at the origin of motion sickness, and a benign vestibular disorder can propel this anxiety to higher levels.

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text:
May pilots receive compensation for performing preventive maintenance under US regulations?
Under FAA regulations, I know that at least a private pilot certificate must be held in order for a pilot to perform preventive maintenance on an aircraft.
May a pilot also get paid by someone else for performing that maintenance, and does the grade of pilot certificate make a difference? For example, is there a requirement to hold at least a commercial certificate to be compensated for the performance of preventive maintenance, or is preventive maintenance solely to be considered an incidental, non-compensatory privilege of any pilot certificate holder of private or higher grade regardless of that grade?
This hypothetical scenario is with the assumption that this is freelance and has no oversight by a certified mechanic. An example could be a fellow pilot casually offering to change your oil or replace a lightbulb for some monetary labor compensation.

All of it is "doing work for others for pay". You seem to be asking "where's the threshold where that goes from casual/allowed/unregulated, to needing all the formalities and apparatus of being an FBO"?

First, it's a little too broad to say that a private pilot can perform preventive maintenance. The full wording in 14 CFR 43.3(g) is (emphasis mine):

Except for holders of a sport pilot certificate, the holder of a pilot
certificate issued under part 61 may perform preventive maintenance
on any aircraft owned or operated by that pilot which is not used under part 121, 129, or 135 of this chapter.

In other words, a pilot can't perform preventive maintenance on just any aircraft. The definition of "operate" in 1.1 could be stretched, I suppose, but the pilot has to have some degree of operational control over the aircraft. Another pilot without that control couldn't do preventive maintenance on your aircraft anyway, whether or not you were paying them.
Beyond that, the word "compensation" doesn't appear in part 43 so it seems not to be a factor in who can perform maintenance, preventive or otherwise. And common sense says that a pilot can be compensated because otherwise a part 91 ferry pilot wouldn't be allowed to top off hydraulic fluid or replace a landing light bulb (for example).

A commercial ferry pilot is exactly the scenario that brought this question to my mind.  I think your point of the "owned or operated by that pilot" says it all.  So yes, you can be paid for the work if you're employed by someone to fly the aircraft to begin with, but you can't just go around offering to replace everyone's landing lights for cash. Great answer.

@RyanMortensen You might be able to, if you did a "I will replace your landing lights and taxi the plane" or somesuch bypass (speak to a lawyer however)

For the record, I'm not planning to do this. The question is for scenario purposes.

The answer you linked says adding oil is not maintenance. It doesn't say changing oil is not maintenance.

@TomMcW Good catch, thanks! I've removed that.

Officially, or unofficially?  As a rule government bureaucracy doesn't deal well with informal arrangements between friends, so officially I'm quite sure the FAA answer is no.
It's like asking the IRS if you can pay your neighbor to mow your lawn:  The IRS would say yes, but they would expect a taxpayer ID and a cut in the form of taxes.  To get that, you'd need a business license, to get that you'd need to show OSHA compliance, and so on, and so forth...
So again no, a pilot cannot "hold out" and charge a fee to perform aircraft maintenance unless they are also an A&P.
However, if you are friends, the preventative maintenance is within the scope of what is authorized for an owner/pilot to perform, and you invite him to your hangar to "help", (while you supervise) nobody will know whether or not you buy him lunch or slip him a crisp $20 for his trouble.  Just check the work and know that if the drain plug pops out and your engine seizes in flight that it's on you.  No finger pointing allowed.
I am not advocating breaking rules, but when you examine the ethics of a scenario as you have in this case, and you know in your heart of hearts that you are in full compliance with the intent, then don't trouble yourself asking for permission from strangers, or from a bureaucracy intended to safeguard rather than restrict our liberty.
A bureaucrat will almost always take the safe way out and say no, so in these sort of cases I advocate the military's old policy of "don't ask, don't tell".
ADDENDUM:
From a couple of the comments it is apparent that my answer was not interpreted in the manner I intended.  The point I was trying to make is, that in matters of regulatory compliance it is important to understand the intent and apply some critical thinking to discern what might be acceptable when you are in a gray area.
To further illustrate let me offer a couple scenarios with a bit more detail –
SCENARIO #1:
Scott is a 20 year old who just earned his private pilot’s license.  He is trying to build hours towards his commercial, and pumps gas at the local airfield to earn money towards flying.  He is a hard worker, loves aviation, and is well liked by the local pilots.  Lately he has “casually offered” to change the oil for some of his customers, hinting at an expectation of being paid.
Is this OK?  NO!  As I indicated above, Scott is holding himself out to perform preventative maintenance functions on aircraft where he is not the owner operator.  The regulations are clearly intended to prevent such shade tree mechanics from compromising safety and undercutting licensed A&P mechanics, while still allowing owner/operators to perform routine and minor operations.  At no time did I intend to suggest this might be OK, and that “nobody will know...”
SCENARIO #2:
Tom is a 70 year old retired engineer and Cessna 172 owner.  He is in good health, but less mobile than when he was young, and had a knee replaced last year.  Carl is a 35 year old ex-military pilot who is now a first officer for a regional airline.  He also owns a 172, and rents a hangar right next to Tom.  Over the last year Tom and Carl have become friends, and often swap flying stories and share tools as they do as much work on their planes as allowed.
Carl noticed the last time he watched Tom change his oil that with his replacement knee it was very awkward for him to get down underneath the engine to access the drain plug.  “Why don’t you let me help you out there Tom?” Carl casually offers the next time they are changing oil.  “I will get that drain plug for you if I can have a cold Coke out of your hangar mini-fridge” he jokes.  Tom semi-reluctantly gives in, watches and verifies that Carl did the work correctly, then fetches him a soft drink as he expresses his thanks.
Is this OK?  Technically Carl performed maintenance for compensation on an aircraft where he was not the owner/operator, and he is not a licensed A&P mechanic.  But really, do you think this is actually the kind of scenario that the FAA is concerned with preventing?  Don’t you think they might have bigger fish to fry?
Tom could have refused the offer.  Or he could have written a letter to the FSDO, or AMDO requesting permission.  Or he could have gone on the internet and asked random strangers what he should do.
But if I was Tom, or Carl, I would simply do it and not lose a minute of sleep wondering if the FAA will find out and I might go to jail for displeasing my government.  No ethical dilemma or safety concerns here, the intent is met, but maybe that’s just me...

Aviation is a heavily regulated field. If you perform maintenance on an aircraft, then you're legally liable if that airplane falls out of the sky. People can and have gone to prison over things like this.

"I am not advocating breaking rules..." That is debatable, to put it generously, especially at the point where the offer of "help" is conditional on receiving compensation for doing so. Any proposition with the phrase "nobody will know" in it should be considered very carefully.

I feel this is just wrong in the aviation case.  The lawn example has no downside or danger.  You can't in any way compare that to something like - aircraft - building bridges - running nuclear attack submarines - and so on.  It's more of a counter-example that shows why you can't fudge around like this in the aviation example.

@Fattie " The lawn example has no downside or danger" So why do US Emergency medical departments treat about 85,000 lawnmower-related injuries per year. Compare with about 1,000 non-fatal General Aviation accidents per year. I don't think the average non-fatal GA accident injures 85 people ... (refs https://pubmed.ncbi.nlm.nih.gov/29395756/ and  https://www.statista.com/statistics/1031941/us-general-aviation-accidents/#:~:text=Fatal%20and%20non%2Dfatal%20accidents%20in%20U.S.%20general%20aviation%202000%2D2019&text=There%20were%20a%20total%20of,233%20fatal%20accidents%20in%202019)

@alephzero, I think you are quoting raw numbers without factoring in the denominator (out of how many potential cases).  I believe there are more people who use lawn mowers than fly airplanes.

@alephzero difference being, lawn care mistakes have immediate effect on the lawn care worker... wheras aviation maintenance mistakes cause delayed effect on innocent third parties.

IRS and state 'revenoors' (both) want taxes on paid lawn care, but you don't need a business license (or even to be a business) to get an EIN, and services performed 'in or around your home' can be treated as a 'household' employee which is simpler to file than other kinds -- just W-2/3 and Schedule H, and maybe 1040ES depending on the amounts. But USCIS separately wants I-9.

@nick012000, yes - and that is why the FAA has a robust program for certifying A&P mechanics.  See my addendum...

@sdenham, I don't wish to debate on whether you think I advocate breaking rules.  I will even admit as much, provided safety is not compromised and the intent is obviously met. I made an addendum to my answer, hopefully that clears up my position for you...

Pondlife's reply above was correct.  The person performing preventative maintenance cannot simply do so on any aircraft; it must be one that he or she owns or operates.  Operational control is the standard by which operation is determined.  If the pilot has operational control by virtue of flying the aircraft, or causing it to be operated, then he or she would qualify.
The regulation does not stipulate issues of compensation or hire for aircraft maintenance.  There is no commercial mechanic certificate, vs. a private mechanic certificate.  Likewise, there is no commercial preventative maintenance, vs. private preventative maintenance.
Can one get paid to perform preventative maintenance?  Sure.  For example, one might own a Cessna 172 which is on leaseback to a local flying club.  One might get paid to fuel airplanes, wash airplanes, and even to do the oil change on the airplane in the course of one's duties at the flying club.  One can also perform maintenance under the supervision of the holder of a mechanic certificate, and do it for compensation or hire.  This is perfectly legal.
As always, however, the devil is in the details, and the specifics of a particular situation matter.
Regardless, bear in mind that even as a private pilot performing maintenance, you're still beholden to perform it to the same standard as any certificated mechanic.  You must do it to the same standard, with the same tools, practices, and procedures called out by the manufacturer and as standard practices and techniques (eg, AC 43.13).  You're also responsible for the same maintenance entries and record keeping expected and required of a certificated mechanic.

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text:
How can I stop being too high or low when on base and final?
I'm a student pilot having trouble with landings, and problems are occurring in the pattern on base and on final;  I am either too high or too low. As a result, I feel I have lost confidence.
I feel like I am relying on my instructor to tell me what to do next instead of me flying the plane. How do I improve this situation?
Also, it has been suggested that I stop using the simulator as this is teaching me bad habits.

Hi @Mike, welcome to the site. I feel your pain, but this is not an answerable question as it's very broad, and opinion based. I suggest you edit, describing some of the specific issues you have to focus it down. In any case I'd drop simulator flying and keep on practicing on the real thing. Try not to overthink it and don't give up. Above all - relax!

Do get off the sim... It's very different flying a real plane. Sims help with practicing instrument procedures... But not much with learning the bits and bolts of flying in primary training. Likely it is messing you up.

You need to focus on sight picture. First make sure your seat is set right before you leave the ground. The cowling is in the same place, take a minute to look out the window and make sure everything is where its supposed to be. Then have your instructor fly a few circuits and pay attention to the sight picture. The angle of the runway, the position of the runway in the window, where the horizon is, etc. Then you try. Just remember the sight picture changes if the runway is narrower/wider or longer/shorter and it takes practice to get right.

The sim can help you to get better at some things (visual flying is not one of them) after you have learned how to do them for real.  Trying to practice your approaches on a sim is almost certainly making it harder for you.

I'm pretty sure we've all been where you are now.  Listen to your instructor (both on the ground before the flight & in the air), and take things one step at a time.  Learn to recognize problems early.  It's much easier to fix a 1 foot mistake than a 100 foot mistake.  Be patient - this may take a few hours.

Thanks for the help. Ron I think you are right about the seat. I battle with the Sling II as the seats dont adjust well. its feels i need to support my back a bit better so I can sit a bit more upright.

I also think the visual perception of where things are when one is on final is important, looking forward to next flight and will put some of these suggestions to practice. Also get my instructor to fly one circuit for me. once again thank you all and have many happy landings.

Everyone's landings suck at the 13hour mark. Practice makes perfect less embarrassing to those watching.

This question may give you some more insight to the flight simulator issue.

@RonBeyer is correct about the seat height and many instructors dont understand the differences in sight picture when th seat height has changed.  It is the very first thing I always stressed on flight lesson one with my students.  On average they solo'ed quicker than others at my flight school.

I think one thing that does not get emphasized enough:
Pilots do not land airplanes!In fact, we try to keep the airplane flying as long as possible!  We systematically rob the airplane of energy (energy from engine power, energy from airspeed, energy from altitude) until the plane can no longer fly, and settles gently on the runway.
But even as the plane is landing, the pilot is still trying to coax it back into the air to remove as much energy as possible.  A big student mistake is to point the airplane at the runway, and try to force it to land there.  That leads to landings too fast, too high, big bounces, porpoising, and sometimes nose-in crashes.
So don't think about "how am I going to land this thing?"  Instead think about "How am I going to remove more energy from the equation to lose altitude and airspeed?"
A landing is a series of precise targets you are aiming to hit, each with less energy than the last one (but each one still with enough energy to keep flying and be safe)
Each target consists of Position (horizontal and altitude), airspeed, and descent rate.  You hit each of these targets at 3 different points on a square (abeam the numbers, downwind-to-base, and base-to-final) Hitting a target that consists of a position + airspeed + descent rate is not easy! But the more precisely you can hit each target, the easier the next part is.

Although I hope I'm repeating the same instructions you've already heard, for the sake of the Site, let me re-iterate the standard instructions for a C-172.

Be level at TPA (airport + 1000 feet), and at a cruise speed of approximately 100 kts.  The runway should be approx 3/4 of the way up your strut.
When you are abeam the numbers, Carb Heat (if applicable), throttle back to approx 1,600 RPM, and pull-back as necessary to maintain altitude (the consequence will be that you slow down).
Watch your speed, altitude and position.  Drop flaps 10° when speed allows, and aim to hit a speed of 85 kts, an altitude loss of 250 feet, and have the numbers at 45° behind you, all at the same time.
Turn the corner to base, using approximately 30° of bank angle.  Continue to reduce speed (by pulling back) to hit 75 kts, and drop altitude another 250 ft. (you're now 500 ft above the runway).  Add Flaps 20 when appropriate.
Turn the corner to final.  You can "oval" your turn if you are undershooting the centerline, but do NOT over-bank if you have overshot the centerline.
Aim for the centerline, acquire a PAPI/VASI, keep an eye on your airspeed relative to approach speed (68 kts).
Watch 3 and ONLY 3 things:

Airspeed (Slowing towards 68 kts)
Centerline (left? right? on target?)
Slope (PAPI/VASI? Light configuration).

Keep repeating "Airspeed, Centerline, Slope" out loud, describe if you're too far/too close on each one, and describe how you're going to correct.  For example:

"Airspeed: 75 kts; too fast; pulling back to slow down"
"Centerline: Left of center; coming slightly right"
"Slope: 3 red+1 white is too low; adding power to slow descent"
(repeat!)

When the runway is made, drop final flaps, engine to idle, and prepare to flare when you're about 10-15 feet, and hopefully right at the numbers.

Remember that your altitudes are 1000, 750, 500, touchdown.
And your airspeeds are 85, 75, 65.

Oh, and for your last part, the best part is that you have to adjust those precise targets based on the wind too!

Thanks I am going to do this. I have not flown for 5 days its depressing. flying again on Wednesday I will post how it went. Thanks you....

The problem with simulators is that they do not have a very wide field of view, so it is hard to train your eye using a simulator. If they develop simulators with full VR panoramic vision someday, that will be much more useful. Some walk-in military simulators are like this, but normal students do not have access to these.
When you look down at the runway, it should be at the right angle. When you go onto final that angle is 3-degrees which is a 20:1 distance/height ratio.
Basically the way it works is as you go downwind you look left (or right) and espy the numbers, if they too are low (ie you are high) you keep heading downwind and gradually descending until it looks right. To learn what "looks right" learn all the distances and altitudes at your home airport. If you know the geometry of your home airport you should know EXACTLY where to turn for any given altitude.
It sounds to me like you do not know this. You need to sit down with satellite photos of the field, a ruler, pencil, and calculator and start measuring until you really know all the angles and measurements exactly. Every good pilot does this when they are a student. Once you learn it for one airport your eye will know what is right and can land anywhere.
This is really a homework and serious study problem. Don't just jump in a plane and wing it--that's how bad, sloppy pilots get made. You need to sit down and master it before you even drive to the airport. I was just sitting with a student yesterday and he showed me his notebook. Wow! Looked like engineering drawings. He had every dimension and angle all plotted out on graph paper in incredibly neat writing. He is going to be a really good pilot someday. That is the kind of behavior you need to emulate.

The HP Reverb G2 is definitely at a point where you feel you are there. You answered in 2016 so that was still a ways off. These days, in VR, looking through the polycarbonate window of a light sports aircraft while you are banking, doing a midfield pattern join in MSFS is so realistic. Only to be experienced.

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text:
Introduction to aircraft performance
How do determine the power available and the power required for an aeroplane in a steady level flight=

This is much too broad.

Can you at least give one solution?

Sure.  Trim the airplane in level flight-  that’s the power required.  Then push the throttle all the way forward. That’s the power available.

Re "Introduction to aircraft performance" -- is that the actual name of the class, for which you are asking a homework question?

yes sir, is that an issue?

yes, it is an issue because you don't say what you have tried to understand, and what is not clear to you after you have studied.

Oh sorry, I am new on this site. I am a first-year Aerospace Engineering student. I haven't taken any courses related to this field but this. I will delete my question.

you should not delete your question, you should edit it and add the relevant information: what you searched on your own, what you found, and why you're not satisfied with what you found. Also, now you jumped to accept the answer, so you can't delete the question.

Power required for steady level flight is glide ratio × weight at a given airspeed.

Power = Force × Velocity = mass × m/sec$^2$ × m/sec = mass × V$^2$/sec

So you work to draw your drag curve at various airspeeds.

Thrust = Drag in level steady state flight.

Then you determine what type of performance envelope you want.  Just like cars, economical or sporty.  Conveniently, fuel burn can also be expressed as Energy/sec or mass × V$^2$/sec and, over a given distance: mass × V$^3$
Generally, you want at least enough excess thrust available to maintain a safe climb rate (in case of downdraft) for a given weight.

None of this actually answers the question (as unspecific as it may be), and along with factual errors (e.g. glide ratio times weight is not power) and the bolding of unrelated terms it reads more as a post geared to SEO.

@Raketenolli this is about as unconstructive a comment as I have ever seen here.  See the equation right underneath the statement "Power required for steady state level flight ... at a given airspeed" Anything wrong there?  Important points were bolded for the benefit of the person asking the question (not you).  Before you cite "factual errors", try reading a bit further.  BTW what is your definition of performance?

Yes, I did read them. But the question is not "introduction to aircraft performance", but "How do I determine the power required (and available) for an aeroplane in steady level flight?". You state that power is force times velocity. Which is true. But then you start multiplying physical quantities (mass) with units (m, sec) for no apparent reason and no additional value. You only vaguely hint at where the force and the velocity that you want to multiply come from. You say the OP should determine what type of performance envelope he wants. Which again, is unrelated to answering the question...

... fuel burn was similarly never asked for and you mention that you "want at least enough excess thrust" which might be remotely related to the part of "power available" in the question, but doesn't actually answer it.
I downvoted, so I felt like I needed to explain why I did so, which was, admittedly, a very sweeping and not very detailed judgement, but if I had wanted to be very constructive, I would have simply answered the question the way I would have wanted it to be answered, but it was already closed.

@Raketenolli thanks for responding.  It just so happens that thrust requirement for level flight (in pounds) can be rather accurately determined by multiplying glide ratio by the weight of the aircraft.  This is a well known technique.  F = Ma.  It works, and is in fact in the question as "power required" and can be directly linked to fuel burn.  Fuel burn is linked to engine size and weight.  This is a starting point for design.

"Vauge hint"  draw drag curve at various airspeeds.  Glide ratios will differ on both sides of Vbg, but, lucky for us, good ol' gravity is constant.  Maybe a good cup of coffee will help us.


text:
Does the FAA have control over private "airparks"?
We were informed a neighbor is planning a 2800 ft. X 150 ft. asphalt "air park" on property behind our home. The end of the runway is to be 360’ from our bedroom windows. As our home is in the curve of the road, neighbors on either side will be even closer to the end, just not under direct fire from planes taking off & landing. She is planning 4 Cessnas (no ideas on the model #), with amateur pilots. The wooded property was zoned “restricted residential”, but the change slipped thru the zoning board without neighbors on all four sides being notified & given an opportunity to voice opinions.  Obviously we are worried about the safety of our home & those of our neighbors in a “crash zone”.  Does the FAA have jurisdiction over such strips?

Do you mean feet (not inches)?   150 feet seems awfully wide

Maybe 150ft includes the apron, not just the strip.

Sorry guys did mean 2800 feet x 150 feet, and it's our understanding all of this square footage is to be paved with asphalt.

Public airports have FAA oversight, private airports don't. Are you really worried that an airplane is going to crash into your house or was that just an expression?

Relevant related question, possibly duplicate; the short answer is "no, the FAA does not have control." I would concur with other commenters that 150 feet is very wide for a short private-use runway. I suspect that the actual runway width will be closer to 50-75 feet, or even less.

@Parker-Proctor this doesn't really answer your original question, but concerning the runway dimensions it's extremely unlikely that the runway would be paved 150' wide. Boston-Logan's runways, designed for heavy jets all the way up to an Airbus A380, are 150'-wide, and 10,000' long. My guess is somewhere in the 40-60' range is most likely. It's possible there's a paved taxiway and the two together could total 150', incl. the grass in-between.

I'd like to explain my downvote: 'Obviously we are worried about the safety of our home & those of our neighbors in a “crash zone”' This question seems to be making an unfounded assertion. It is not obvious at all that neighbors should be concerned about a plane crashing into their house. This distracts from the real question-- FAA jurisdiction over airport sites-- and could derail good answers with a political discussion.

It would be much more productive to go back to the zoning board and discover why you were not given a chance to lodge an objection. This sort of thing is the bread and butter of local politics, and local news just love stories "residents concerned about new airport".

The FAA only has jurisdiction once a plane is in the air and they are not anxious to restrict traffic based on complaints. They have airport design guidelines for larger facilities. On the ground it is up to local authorities and zoning is the normal means of control.


text:
How do the hydraulics in an airplane have constant pressures? What is creating resistance to the pump flow to create constant pressure?
my question comes from the A320 specifically, and I also suppose Boeing jets. Whenever you check the hydraulic system pressures on an A320 it says 3,000 psi, even when you move the flight controls. How is this pressure a constant 3,000 psi no matter what? What is creating the resistance to create this pressure? Thank you very much!

The hydraulic system contains a pressure regulator device which maintains almost the same source pressure to the cylinders across the full range of flow rate demands, regardless of what the pressure being developed by the pump might be.
In practice this would mean designing the pump to develop a minimum of, say, 3100 PSI across all engine speeds and then putting in a pressure bypass that automatically flows the extra 100 PSI back to the pump sump.
When the flow demand on the hydraulic system is high, the pressure bypass progressively closes so as to maintain 3000 PSI throughout the system.
Another way to do this is to control the pump motor with a pressure sensor that automatically cycles the pump motor anytime the system pressure falls below 3000 PSI. What you will hear in times of high hydraulic system demand is a surprisingly loud VOOOOT! VOOOOT! VOOOOT! noise as the pump cycles on and off to hold the source at 3000 +/- (some value) PSI, which I have indeed experienced on the 320 upon landing (when the flaps, spoilers and whatnot are all being retracted).


text:
Can I log a VFR XC toward 141 commercial license while simulating instrument
I flew last night with a friend to split time. Half the flight I wore foggles, half the flight he did So we could both be PIC And both have approach/landing practice.  Could I log all of that simulated instrument time into a 141 VFR XC commercial flight lesson?

I would say that time spent navigating by reference to instruments alone does not meet the intent of VFR.  Can you give us an interpretation of 61.51 that supports your objective?  And does your school agree?

Logging PIC/SIC time is straightforward.  Your scenario, commonly called “splitting time”, is widely accepted, as long as you scrupulously follow the rules in part 61.
Logging XC is a little more complicated; only a pilot who both takes off and lands for the same leg can do that.  That means at most one pilot can log XC time.
But being able to log time under 61 doesn’t automatically mean you can use that time as credit toward a 141 program. That depends entirely on the specific program syllabus approved by the FAA, so we can’t answer that here.  You’ll have to ask your CFI or maybe Chief Pilot to know for sure.


text:
How services such as FlightAware know ground speed of a GA airplane
There is a question Why is the speed graph of a survey flight a square wave? with a Piper PA-31-150 accident, and its ground speed graph is part of the question.
This made me questioning - how the gound speed of GA aircrafts is known to the services? I briefly searched for the basic info GA transponder sends, and did not see the gound speed in there. Plus, to know a ground speed, such measurer should be installed on the aircraft - either a sat-nav, or an inertial measurer, or something else - and it needs to be connected to the transponder as well.
It can be that the services calculate it based on the locations sent, but I did not find GA aircrafts send coordinates either.
And another question - if this data is sent to the services, why the information might be that valuable to an aircraft - so they both calculate it and send it? I imagine, the true speed is the one that is important, not the ground speed - so, why sending it at all, even if the aircraft has the data onboard? To measure the fuel we can use time and air speed/RPM, why else we would send it - and have it on the service?

Since 2020, all aircraft in most controlled airspace are required to have Automatic Dependent Surveillance-Broadcast (ADS-B) out. This means they are required to send, among other information, their GPS coordinates and altitude at least once per second. (See 14 CFR 91.225)
Using these GPS coordinates, which contain time and position data, ground speed can be calculated.
The data GPS data is collected mainly from community "feeders" who build ADS-B recievers and transmit the data to sites like flightaware, adsb-exchange, etc. If you're wondering why someone would do this for free - well some people think it's fun, and some sites offer premium memberships in exchange for feeding data.
GPS data of the accident aircraft seen here is from the ADS-B transmitter.

Regarding your other questions - the data is not even available to the crew on board. It is purely for ATC separation of aircraft in controlled airspace, as well as dinging people for illegal stunts or unauthorized entry into certain airspaces. If you have ADS-B "in" you can also use this to augment your situational awareness by knowing the location of nearby broadcasting aircraft.
Note 0: Heading is calculated simply using a straight or smoothed line between the GPS "hits". This is not entirely accurate since aircraft usually have at least some wind correction angle relative to their ground track. During aerobatic maneuvers and accidents the actual heading (that is, the direction the nose is pointing) of the aircraft is unkonwn and can only be guessed based on external knowledge of the aircraft attitude.
Note 1: ADS-B and most other surveillance methods cannot calculate "air" speed (that is, how fast the air is flowing over the aircraft). This is the speed shown on the airspeed indicator of an aircraft and is dependent on the relative wind. Consider a Cessna 172 flying at 100 knots indicated airspeed into a 50 knot headwind. The cockpit will register 100 knots, but the groundspeed is only 50 knots.
Note 2: GPS is transmitter via an ADS-B transmitter, which is a simply on-off device in the cockpit. It transmits the GPS coordinates to anyone with an ADS-B "in" receiver. This GPS data is used for tracking and surveillance but cannot be used for navigation (as far as I know).
Note 3: The rules governing who needs ADS-B are slightly more nuanced than I stated above, and I believe any aircraft which has ADS-B installed must turn it on during all operation. The "controlled airspace" restriction simply means aircraft without ADS-B are prohibited from many areas in the USA National Airspace System (NAS).

Great answer! Thank you! I was not aware the ADS-B has its own GPS chip to embed the data into the transmittion. However, it makes perfect sense for the ATC to have the coordinates - it is indeed very valuable info to them!

@Mykola not so much "has its own GPS chip" as "needs to be plugged into a compatible GPS unit", as I understand it.

@hobbs but if it needs to be plugged in - it means you have to have a sat-nav instrument in your plane - which does not seem to be a requirement?

I'm not sure the answer to what you guys are discussing, but I just want to point out that you can get a "GPS chip" for $18 on amazon (search "GPYes"), so it's not like GPS is some unattainable technology. Obviously the technology used for aircraft surveillance will be higher price and quality but still nothing extraordinary to add to a transponder.

@codenoob The issue isn't as much the GPS receiver, though that will cost you about $400 extra in a ADS-B out transponder, it's the fact you have to mount a GPS antenna on the top of your plane, which will cost you another $300 to buy, and then maybe $1000 in labor to cut a hole in the roof, install, seal the antenna, route the cable through the interior.

@user71659 Gotchya! Good point.

@codenoob if it costs $18 - or even $200 - this is today's price. What about the aircrafts that were made yesterday?

Not sure I follow your Q, sounds like your asking what's the equivalent of $18 in 200X?

Which aircraft can be tracked?
The only aircraft appearing on tracking sites are

The ones controlled by ANSP, usually they broadcast ADS-B messages in addition of being tracked by SSR stations. All commercial aircraft are tracked over land, and often over oceans. However in the latter case they must use space-ADS-B to be visible, as SSR stations are mostly on land.

The ones not controlled (of which GA aircraft) but having their transponder switched on or broadcasting ADS-B (or FLARM) messages. They must be in sight of a receiving station, aircraft flying low may escape detection by SSR.

How is ground speed determined?
Aircraft positions are collected by tracking sites at regular intervals (a few seconds). These positions are relative to the ground. The distance between two positions can be calculated, the ground speed is obtained by dividing by the time between the two transmissions.
Is ground speed useful for aircraft crews?
It is the only way to determine the time of arrival at the next waypoint or at the airport. Even before GPS, avionics was used to compute the ground speed, usually with inertial systems.
Details follow about:

What are ANSP, ADS-B, FLARM, SSR
How are positions determined.

How are aircraft positions collected?
Flight tracking sites get they information using two categories of feeds:

Their own network of ADS-B receivers. They started with this technology by federating individual ADS-B receivers owned by hobbyists. ADS-B is a voluntary transmission from the aircraft using a transponder or an equivalent system (UAT) containing the aircraft altitude and position and other data. A in ADS-B is for automatic, meaning the transmission is automatic, D is for dependent, meaning ADS-B relies on an external source for the information to be transmitted, e.g. on a GNSS receiver (GPS, Galileo, etc) to get the position. FLARM is a technology somehow similar to ADS-B and collision avoidance systems, used by small aircraft and gliders.

Data received by ANSP (air navigation service providers), using a subscription, likely for a price. ANSP can receive aircraft position using multiple technologies:

SSR (secondary surveillance radar). The ground station interrogates the transponder aboard the aircraft. The transponder answers with its altitude. The SSR station is able to determine the position by classic radar ranging. That's how most aircraft are still tracked today by ANSP.

ADS-B data, ANSP receive ADS-B using SSR stations and UAT receivers. The aircraft must broadcast ADS-B messages spontaneously. This is how aircraft (and UAV) will be tracked in the future by ANSP. ADS-B receiving stations are land-based.

Space-based ADS-B, ANSP receive data from Aireon, which manages ADS-B receivers hosted on Iridium NEXT satellites. This is a complement of land ADS-B for aircraft out of range of land receivers, e.g. flying over oceans or deserts.

Multilateration, ANSP manage their own network of multilateration receivers (MLAT and WAM). Multilateration consists in simultaneously receiving the aircraft transponder or ADS-B signal at different positions, and determining its position by comparing the different times of arrival.

ACARS, aircraft may send messages to ANSP, or to their airline operations management, for the purpose of planning and maintenance. These messages can be sent to receiving stations on land (VHF link) or in space (Satcom link). Tracking sites are interested in ACARS mostly to know the actual departure and arrival times.

FLIFO (Flight Information) from flight reservation systems, for general flight information from airlines. FLIFO is used to know future flights.

For all sources, but SSR, the position is determined aboard the aircraft using GNSS and transmitted. For SSR the ground station determines the range, the bearing, and the ground speed, this is less accurate.
Tracking sites also receive flight plans from ANSP, they can associate an aircraft identifier with a flight plan.

Thanks for the answer! So, would a GNSS device be separate to ADS-B? Does it mean the plane has both installed? Would it (the coordinates transmitted over ADS-B) be optional in some regions - and mandatory in some else?

@Mykola: When a mode C transponder is used for ADS-B Out transmission (usual case), ADS-B Out is a software application receiving the position from an independent GNSS hardware and using the transponder as a transmitter. For details see this. Position is required (§5.1.1.1.1 of Annex 10 volume 4).

@Mykola: See also What's required for the ADS-B to function? A GPS or Mode S Transponder?. Also note a GNSS is not required per se, just a mean to get a precise position (but currently it is a GNSS)

These services are based on ground based radar and transponders -- not GPS or SATNAV.
The transponder (Mode C) sends out an ID and pressure altitude.  The ground based radar is good at bearing and range -- but not altitude.  Combining these gets it a 3D fix on the aircraft.  Tracking that over time gives ground speed.
Newer technologies Mode S and ADS-B and GPS all improve on this, but the old-school answer is radar + altitude.

I did not know FlightAware or FlightRadar24 have radars on the ground - I always thought they rely on ADS-B of their networks plus the networks of volunteers. Do you have more information on the radars positions and types? Those are not cheap and require a license to operate as they are not passive and the radiating power is normally high for non-license equipment.

Perhaps they are operating off of a network of ADS-B receivers.  I thought that the government operated radar stations provided data to sites like those listed.  I could well be wrong.  Actually, it looks like a bit of all of the above...
https://www.flightaware.com/about/datasources/


text:
What is the best combination of airfoil shape for flight in ground effect over water?
What is the best airfoil shape for flight in ground effect over water?

Why closed? The principle of GE vehicle is well known. Which airfoil, which angle of attack to use are valid questions. An hydrofoil is similar to an airfoil. Related: Wing in Ground (WIG) Effect Vehicles.

In my opinion it's unclear because it has several questions, each of which has minor problems.  Overall the question fits the "What's your favorite?" or “I use ______ for ______, what do you use?” types that are listed as questions to avoid.  My suggestion would be to break up or simplify the question so it's clear what you really want to know.  Another way to improve it might be to focus on how you choose the airfoil, not what you should choose, or instead provide specific acceptance criteria so we know what exactly you mean by "best airfoil".

I would second @CodyP 's suggestion.  This needs to be broken up into a few questions so that all issues can be addressed separately (possibly with links between them.)

The question is still vague.   By best, do you mean most widely used, highest coefficient of lift, or best lift to drag ratio?  How important is it to have aerodynamic center and coefficient of lift relatively constant for various heights?  What are the operating speeds (Reynolds number), angle of attack, and ground clearance are we talking about?  Typical Reynolds numbers can range from 310^5 to 210^6, angle of attack might be 4 degrees, and ground clearance between 5 to 100% of the chord length

This question has been the subject of a lot of research over the years. You may find this paper in particular to be helpful in answering your question.

Optimal airfoil shape has nothing to do with the fact whether the aircraft is ground effect or not. What matters is getting the minimum drag for the operating CL

There are three considerations for this design:

Airfoil shape
Aspect ratio
Dihedral/Anhedral

Airfoil shape: high lift undercambered thick and very forgiving - good idea near the ground
      Gottingen 436, NACA 4412
Low aspect ratio: lower stall speed, better compression lift from ground effect, more
     stable in pitch
Anhedralled wings:  this actually provides more roll stability in ground effect as the
      LOWER wing has more lift.  Anhdralling also helps "trap" more air underneath the wings
      for greater lift.
Ground effect designs would be similar for travel over flat land or water.  Good info in links
provided by @mins and @Juan Jimenez.

The Achilles Heel of WIG is the instability in pitch as the plane comes out of ground effect and the center of pressure moves forward. Planform shape is a real target of opportunity for making WIG more usable.

Spruce Goose seemed to do OK.  Not sure about that reverse Delta, or constantly flying low.

I think it left performance gains on the table, though. Anyway, WIGs are cool.


text:
Why does the Hinch Mountain VOR (as an example) have void areas below certain altitudes published in the U.S. Chart Supplement?
I was digging around the SE region Chart Supplement, and I was reading KSRB (Sparta, TN), and this "VOR unusable" listing is contained in it:

The sectional chart shows that it is nearly on top of a hill. I've made some visual marks on this to help everyone visualize.

Hench Mountain is a Low Altitude VOR, so by normal standards, service should be clear all the way around at 1,000 ft above it's altitude:

Why are there unusable areas more than 1,000Ft above the elevation of the VOR?  I've flown over it, and there are no obvious obstructions, it sits on top of a flat hill as you can see in this video I found on Youtube.

Google maps looking west... I could see there being obstructions in other directions but this seems pretty clear. Though it is the lowest restriction.

I can't cite a specific cause in this case, but VORs are subject to multipath and other propagation errors. These almost always occur at the lower altitudes. If the FAA flight check shows the omnibearing to be outside the allowable variation, that area will be declared unusable. In this area with highly variable terrain a strong reflection from a slope 10 to 40 degrees off a course could cause enough multipath to 'bend' the omnibearing by several degrees.

See guidance reversal.

Either multipath including refraction induced  errors  or blocking/masking by terrain.


text:
What is the difference between a pressure switch, high-pressure control, and low-pressure control in a landing gear hydraulic system?
This is an Arrow II landing gear diagram.
In the diagram, the high and low pressure controls look like check valves.  The pressure switch is unclear.
What are these three items, and what purpose does each one serve?

Does the manual offer no explanation?

@JWalters the plane's information manual does not, but JohnK linked this in another related post.  http://www.mikeg.net/library/files/pa28-service.pdf : I am reading through it now.  Perhaps it has what I'm looking for.

The pressure switch looks to activate in the retracted position as a cut out when the flow becomes impossible, probably at fully retracted position. This would mean that the pressure needs to be maintained in the retracted position, which suggests in case of leak or in case of cooling at high temperature the pump will start again. I am not sure of my answer, this is a just a speculative thinking!


text:
Why do TACANs not have a symbol for compulsory reporting on IFR Enroute Low Altitude charts?
I am studying the IFR Enroute Low Altitude legend, and I noticed that all NAV Aids other than TACAN have a compulsory reporting point icon.

They do appear on the STAR/DP legend.

Why do TACANs not have a compulsory reporting point icon on the STAR/DP, but not IFR Enroute Low Altitude?

VOR frequency  108.00 to 117.95 MHz.  TACAN frequency 960-1215 MHz.  So even when shown, civilian radios would not pick them up.  I can't talk to military operations, but I know I can't report a point that I can't tune in.  Not even sure my GPS would identify them for me.

Keep in mind that the chart legends aren't the end of the story, because they're only the abridged version! If you really want to study the chart symbology, the Aeronautical Chart User's Guide is one of the FAA's best publications ever.

TACANs are for military use. VOR or VORTAC are the civilian equivalent.  Civilians can't generally tune in TACAN.
This wikipedia article has more details.  https://en.wikipedia.org/wiki/Tactical_air_navigation_system

Don't the FAA enroute charts serve both civil and military users?

Nope. Military training routes are identified on civilian charts. No TACANs are shown tho. VOR, VOR-DME and VORTAC, but not TACAN.  You can see the charts here https://skyvector.com  Military have their own charts.  https://www.nga.mil/ProductsServices/Pages/Aeronautical-Charts-and-Publications.aspx

"The Aero Browser – ACES (Aeronautical Content Exploitation System) is a map based web site that provides enhanced web technology for users to access multiple geospatial intelligence and aeronautical information databases and to "package" the information into user-specified formats. This capability provides access to data that comprises the many NGA aeronautical products and crosses over the traditional lines of AAFIF, DAFIF, FLIP, or Intel Imagery and makes all available as needed, with just a few clicks of the mouse.This site is open only to U.S. military, ..."

@CrossRoads could you elaborate on the point that the reason is that military operations would never be reporting to ATC so it is thus irrelevant to have a TACAN be compulsory reporting?  I think that's the main takeaway, I just want it more clear please and then I will mark it accepted.  Even that doesn't explain why one chart has it and the other doesn't though.

@Ryan Mortensen - I do not see where CrossRoads has said “that military operations would never be reporting to ATC”. Military aircraft communicate quite a bit with civilian ATC. Especially when they are entering civilian or joint controlled airspace. Civilian aircraft can even communicate with military ATC. This does not happen as much. But, it is still necessary when flying through their airspace or SUA. On the other hand, civilians can not use TACANs as a NavAid. They will put it on sectionals if the TACAN can be spotted from the air as a visual reference point (just like private airfields).

@CrossRoads, the military uses the same IFR charts as everyone else.

This answer does not address the question. There is such a symbol on the STAR legend, so simply saying "it isn't relevant" isn't correct. And there is the fact (pointed out by @MichaelHall) that the chart is meant to be used by military pilots as well.


text:
What is the proper way to update the time enroute in an EFB system without the assistance of any GPS technology?
I remember training with paper nav logs and the student would have to update the actual ground speed based on time between two waypoints in a flight.
In an EFB, what is considered the proper way to do this per FAA standards?
Does the student need to e-mail and print the automatically-generated navigation log, and use it in a paper form with an E6-B flight computer along the route of flight?
If they are using GPS, does that suffice for ensuring they're staying updated as long as they calculated expected fuel burn at each waypoint based on GPS-indicated ground speed?
The software we use is ForeFlight, but surely this question is not limited to ForeFlight alone.

If you have foreflight connected to a GPS receiver or use the internal GPS (if available) this information is updated for you within foreflight.


text:
Why would it be logical to call clearance delivery prior to CTAF during an instrument approach?
I am quoting this directly from the FAA's Instrument Procedures Handbook publication.

"The communication strip provided near the top of FAA approach charts gives flight crews the frequencies that they can expect to be assigned
  during the approach. The frequencies are listed in the logical order
  of use from arrival to touchdown."

Here is the communications strip from the plate in the prior page:

Never once have I been trained to contact clearance delivery prior to CTAF during the execution of an instrument approach procedure, much less any time other than when I am trying to get my initial IFR clearance.
Why is this listed before the CTAF?  Would a tower or ground frequency not be more appropriate and would it not be more appropriate to have it in logical order as the last frequency, not the second-to-last?

Note that it is an untowered airport, so you'll have to close your flight plan—it might still make sense to ask why it is listed before CTAF though (in the duplicate it is last).

The other question is asking purely about the existence of clearance delivery on the approach plate.  A portion of my question was indeed a duplicate, so those parts have been removed and now the question only reflects matters of the order of appearance rather than the reason for appearance.


text:
What is the procedure to appeal an FAA DPE who conducts exams in a manner that conflicts with certification standards?
Does the FAA have a formal process to allow applicants and instructors to appeal a DPE who does not conduct pilot examinations in a manner consistent with the ACS/PTS guidelines?
If yes, how does the process work?

Edit: I decided to add this disclaimer five years after having asked
this question -- I have had no issues with any examiners I have tested
with personally or sent students to, but I have heard my fair share of
accusations of unprofessional conduct by examiners in the industry
which lead me to ask this out of curiosity.

Contact your local FSDO. Keep in mind that the aviation community is very tightly knit. Have all of your evidence ready when you approach the FSDO. If it becomes a matter of he-said she-said the DPE will likely face no action. If you can prove the DPE did something wrong you will likely destroy the DPE's reputation and end their career.

Based on the little bit of time I spend researching this myself, it appears as if the FAA has some sort of complaint hotline.


text:
How do streamlines look on the wing of a hang glider?
How do streamlines/flow look like on single surface wing of hang gliders, especialy on the lower side?
Has anyone installed tufts or done CFD analysis on this?

Anyone? I'm sure someone, somewhere has installed tufts on a hanglider wing. What, specifically, are you looking for, an image of the tufts in flight?

A floppy Rogallo wing, or a more modern battened wing?  These days, some even have a noticeably thick leading edge extending back pretty far: not at all what you might mean by a "single surface wing."

The lower side isn't the one that stalls, but circulation of air underneath a thin undercambered wing may be of interest.
Thin undercambered wings go back to the earliest days of aviation, providing the most lift at low airspeeds.
Analysis of the flow underneath may show a bit of circulation up and into the underside, providing a bit of drag energy recovery in addition the the lift from higher (ram) pressure underneath the wing.
Full scale hang gliders have sufficient Reynolds numbers to also generate "top lift", which is lost in stall.  This is why "tufts" are usually placed there for study.


text:
Trying to identify an aircraft from a photo
I'd like to know if anyone can identify an aircraft from this photo. The man in the photo is my grandfather Joseph White. He didn't talk about what he did in the war and we have been trying to put the pieces together for years. Any assistance would be appreciated. This plane might have been captured so it's a larger pool of aircraft than I would be aware of.

I think that heavy bomber jacket will rule out the Pacific theater -- you might wear something like that immediately before takeoff (cold up high) but not on the ground where it's 80+ F and 90% humidity -- and he doesn't have his goggles, helmet, or oxygen gear on.

Definitely a P-38 Lightning, no question about it.  Or the photo-recon equivalent.

Did you know that StackExchange also has a genealogy site?  You may be able to get more help there now that you know this is a P-38.  Fold3 is great if you're trying to find military records.

Based on the wing/canopy position and yoke rather than joystick, I think this is some version of the Lockheed P-38 Lightning.  Everything I can see in the photo agrees with what I can find online in terms of canopy style, relative position of the wing leading edge, and the relatively unusual (for WWII era) yoke primary control.
http://warbirdsnews.com/warbirds-news/found-lost-squadron-p-38-piloted-by-lt-col-robert-wilson.html
And what might be another photo of the same pilot, credited as the 475th Fighter Group, actually dressed for work:

P-38s of various generations were flown in both Europe and the Pacific -- including the Aleutians, where the heavy jacket would be more appropriate than the Philippines or Coral Sea.  They were, as far as I recall, not flown from carriers, however, so it would be an Army (before the Air Force split) or possibly British livery aircraft; that's not discernible in this tight crop.

I am 99.99% certain you're right - looking at the way the canopy opens and that hole right in the wing root all match the P-38. Some images would enhance this answer.

the hole in the wing root fairing is a perfect match. I'd say 99.999%

And as a sidenote, all of you should do yourselves a favour and read up on the designer of this plane. Legendary.

What's the hole for?

@Mazura I'm not sure.  Possibly cockpit ventilation, but that might be a good question to ask separately.


text:
Will the blade angle of a constant speed propeller be at its least angle (fine pitch) during full throttle and prop full?
During low power settings, low throttle setting and prop full during taxi, the blade angle will be at its finest pitch. As we increase the throttle for take-off, will the blade angle remain in its finest pitch to cater for increasing RPM ?
Will the propeller be at its finest pitch at full throttle & full prop setting ?

At stand still, maybe, but more likely no. At rotation, almost surely no. Depends on aircraft.
Moving forward reduces the angle of attack of the blades for the same pitch, and it is the angle of attack that determines how much force the blade is converting to thrust.
When you advance the prop lever, the blades will be full fine (low incidence) so they produce less thrust and there is excess torque to accelerate the propeller to the target RPM. But

When the target RPM is reached, the governor will increase the incidence to convert the excess torque to power and stop accelerating the propeller.
When the forward speed increases, the governor will increase the incidence to compensate for the decrease in angle of attack due to speed to keep the thrust, and torque constant, otherwise the prop would again accelerate (a fixed one does).

At stand-still, the engine might or might not be able to reach the full RPM. But the maximum power the engine can produce is proportional to the RPM, and you want to have full power for take-off, so using a propeller that does not allow the engine to reach the full RPM before or just after the aircraft starts moving is a design mistake. And as we said, once the RPM is reached, the pitch starts increasing.

Prop full forward means fine pitch, so when the throttle is pushed full open the engine can spool up to its maximum rated RPM and thereby develop maximum power for takeoff. The fine pitch stop is set so as to prevent the engine from overspeeding at full throttle conditions.
With the throttle still wide open, deepening the pitch angle (pulling back on the prop control) will increase the torque load on the engine and cause it to slow down.
With the engine thus slowed down to a lower RPM setting and the throttle still wide open, pulling back on the throttle will cause the prop governor mechanism to decrease the prop pitch, so as to automatically maintain that RPM setting.


text:
What are these things on the horizontal stabilizer on a Diamond DA40?
What are these things encircled on the horizontal stabilizer on the Diamond DA40? And why are they used from an aerodynamic point of view?

Source: grupooneair.com

As explained in a related post:
The canted tips of the original DA42 are working like an anhedral and create a compensating positive rolling moment for the vertical tail's negative sideslip-induced rolling moment. Ideally, the whole horizontal tail would have anhedral, but it was preferred to keep the elevator hinge line straight.
From: Why don't horizontal stabilizers have winglets?

Aside from the eloquent discussion of reducing "negative side-slip induced rolling moments" (putting larger spats on the wheels would do that too), delving into the lost art of horizontal stabilizer design has yielded an interesting thought:
Under normal flight conditions the tail usually exerts a downforce to keep the center of pressure aligned (longitudinally) with the center of gravity.
However, in situations of excessive positive AoA, such as stall/spin events, tail upforce is required to help the nose down.  Putting anhedralled endplates on the tail is a rather ingenious way of making the tail "bigger" (greater coefficient of lift) when saving upforce is needed, while making the tail "smaller" (lower drag coefficient-vortex mitigation) in a normal flight regime where downforce is required.

Inspired by what a young Clarence Kelly Johnson did with a new airplane that had large nacelles ahead of the wing.  Changing the smaller 3 fin tail of the Lockheed Electra into an end-plated horizontal stabilizer (with 2 vertical fins) greatly improved the stability characteristics.


text:
Why do we turn on fuel pump before descent in Diamond DA40?
The checklist procedure is:

Electric fuel pump ............. on
Mixture ............. rich
MAP ............. 15 in of Hg
RPM ............. 2300

Why the AFM says to turn on fuel pump during descent and not during climb?

Possiblt related: https://aviation.stackexchange.com/q/21993/42636

Won't post as an answer, but the most likely reason is there was a fuel flow issue found during cert testing in the descent configuration at a low fuel level and a nose down attitude, and could result in the tank inlet becoming unported momentarily when fuel sloshes around.  The boost pump is just there as insurance to restore flow to the EDP as soon as possible after such a thing happens to minimize pressure fluctuations in the system.  Such flow interruptions would be tolerable on a carbureted engine that can run half a minute on float bowl contents, but not with an injected one.

AFAIK, every low-wing plane requires the boost pump to be on during takeoff, climb, descent and landing.
This is a safety measure. When you are flying low and slow, the consequences of the engine-driven fuel pump failing can be dire, so the added safety is worth a bit of extra wear on the boost pump.
During taxi, you want the boost pump off so you can detect a failure of the engine-driven pump while you’re still safely on the ground.
During cruise, you have sufficient altitude to safely turn off the boost pump and reduce wear. If the engine-driven pump fails, there is plenty of time to switch the boost pump back on and restart the engine; it may even restart on its own due to the prop windmilling.
High-wing planes generally don’t require running the boost pump (if they even have one) during these phases because gravity feed is a sufficient backup.

This answer, although a good one, does not address the peculiarity of the "boost" pump being requiered during descent, but not during climb.

@Jpe61 The DA40 POH I found says in the takeoff checklist to keep the boost pump on “until above a safe altitude”. I think that counts as a climb. And when you may be descending below a “safe altitude”, you turn it on again. My answer covers both.

Ok, the question should be fixed/amended then, as it now suggest any climb/any descent. There is difference between climb out and cruise climb, as there is cruise descent and descent to land. I only have the DA20 POH, and even that is lost

The previous answer stating that it is standard procedure on a low-wing aircraft to turn the electric/aux fuel pump on for takeoff for safety and to turn it on for descent to prevent vapor lock during low power settings is correct.
Diamond has a bit more to say about it. Diamond's descent checklist and climb checklist both call for the electric fuel pump to be turned on to pressurize the fuel to prevent vapor lock at high altitudes.
From the Diamond DA40 Aircraft Flight Manual Normal Operating Procedures Page 4A-32:

4A.3.11 Descent
Item #4 Electrical Fuel Pump............ ON at high altitudes
CAUTION: Operation at high altitudes with the electrical fuel pump OFF
may cause vapor bubbles, resulting in intermittent low fuel pressure
indications, sometimes followed by high fuel flow indications."
4A.3.8 Climb
Item #8 Electrical Fuel Pump............ ON at high altitudes
CAUTION: Operation at high altitudes with the electrical fuel pump OFF
may cause vapor bubbles, resulting in intermittent low fuel pressure
indications, sometimes followed by high fuel flow indications.

Unless you just took off from a high altitude airport, you are not usually at a high altitude when you are turning the electric fuel pump off during the climb check.
When you start descent you often are at a high altitude, so according to Diamond you would turn the fuel pump on.

The most likely reason is, that during climb, the engine will, of course be running on high revs, and so will the engine's mechanical pump. It will most likely also be operating at better efficiency. For the fuel system & engine combination in question, the engines own fuel pump is not able to ensure sufficient fuel flow (unwanted lean condition) or pressure (possibility of vapor lock) to the engine at low revs, the descent attitude may also be a factor, so the electric pump is used as a backup.
General rule in aviation is, that if a system is not necessary for the safe operation of the aircraft, it is not used to save energy and the system from wear. This does lead to a lot of switch flicking...

I find it very hard to believe the mechanical fuel pump can't keep up with fuel demands in any circumstances

So do I, but since pretty much any piston powered aircraft has an electric fuel pump, and it is mentioned as an item for varying phases of flight, well, you draw the conclusions. In most cases it is there for redundancy, but the arrangement here  suggests other reason than ensuring fuel flow in case the mechanical pump fails. I  edited in the possibility of vapor lock, wich would fix the possible problem that while fuel flow might be sufficient, the pressure would not be high enough to keep vapor lock in the system.


text:
Why is aspect ratio important to pilots?
Aspect ratio is mentioned in chapter 1 of AFM .. why do pilots need to know this and its specific value; what should a pilot derive from that value?

I’d bet few pilots even know what it is let alone know what the AR is of the plane they fly.

@Jim: Well, I do know what it is, but not from anything to do with flying :-)

@jamesqf - Yes. I’m sure there are a good few who do. But percentage-wise not so many.

Why do you assume that pilots "need" to know everything that appears in some book by the FAA?  Pilots don't "need" to know anything about aerodynamics or flight dynamics.  For example, many falsely believe that lift is greater in a climb than in level flight- yet somehow they manage to fly ok. Asking what pilots "need" to know iin order to fly well can only lead to highly opinionated, subjective answers.  Better to rework the question to ask "How might a pilot benefit from understanding what aspect ratio is and how it affects an aircraft's performance and handling", or something like that.

Plus if you only are going to ever fly one model of plane, you surely don't "need" to know anything about how a different model of plane would fly differently, and why--

@quiet flyer: If lift is not greater in a climb, then why would the aircraft climb?

@jamesqf -- https://aviation.stackexchange.com/a/56476/34686

In power planes high aspect ratios usually mean better climb performance for the  available power, and similarly, a flatter glide.  Also better efficiency overall at altitude.
It's nice to know because it lets the pilot anticipate certain flying behaviours (like a flatter glide). By way of direct comparison, if someone puts you into a plane with a low aspect ratio, like a Piper Cherokee, you can expect a steeper glide and more of a tendency to drop out of the sky on landing than its higher aspect ratio Warrior sibling, and having the same engine and at the same all-up weight, you can expect the Warrior to have a somewhat better rate of climb.

Thanks for explaining the practical impact; I never really got it until now!

Yeah it's why the Luscombe 8A performs so well on only 65 hp.  Nice long wings.  Meanwhile, the "short wing" fabric covered pipers, like the Tri Pacer, are well known as flying bricks. On the other hand, the low aspect airplanes will have generally snappier roll control.

Where in handling will a large aspect ratio make itself noticed:

Roll damping. The airplane is sluggish in roll, with high lateral stick forces in case of manual control.
Adverse yaw: The airplane will need a large vertical and ample rudder to keep the ball centered when rolling at low speed.
Low maximum load factor: Span means wing mass, and large root bending moments. A plane with a high aspect ratio will fly straight well but be poor for maneuvering.
All optimum speeds will be shifted to higher lift coefficients when compared to a lower aspect ratio airplane, meaning they will be nearer to the airplane's stall speed.
Low power-to-weight ratio: The lower drag will reduce the need for installed thrust. Conversely, if the power-to-weight ratio is the same as that for a low aspect ratio plane, the one with the high aspect ratio will climb much faster and steeper.
Long approach and noticeable ground effect from the low drag at low speed.
Special landing technique in crosswind: Definitely crab during the approach and kick the rudder on touchdown to align the fuselage with the airstrip. Do not attempt to land with one wing low.

I'd argue the short wing (of the same area) has more "noticeable" ground effect. High AR makes the airplane glide well, and especially well over the runway, sometimes making landing harder; yet the change is greater for low AR: it approaches like a brick but over the runway it suddently flies.

@Zeus: Right, the difference in L/D between approach and flare will be greater with a longer chord, but the absolute distance until speed bleeds off enough from equal starting positions will make the high aspect ratio airplane glide much further, so its absolute landing distance will be longer due to ground effect.


text:
What is vapor lock?
Vapor lock occurs in piston engines especially during summers.. before starting engine we prime it and the engine starts but as soon as we reduce it to near idle or just above idle, engine tends to shut down. to prevent engine from shutting down, we quickly turn on the electric fuel pump and after turning on fuel pump and increasing throttle a bit, engine doesn't shut.  curious to know what's happening behind it ?

What have you found in your research?

You don't start with the boost pump on already? Normally you have the pump running and use the mixture to prime, then idle cutoff while cranking, boost pump still on, and go to rich as soon as it catches.

what causes vapor lock?

Fuel pumps found on GA planes are designed to pump liquid fuel.  They won’t pump fuel vapor.  Vapor lock occurs when fuel in the supply plumbing gets heated above the fuel’s boiling point, turning it into vapor. No bueno.
2)Turning on the electric pump may help in one or both ways:
A) increasing fuel pressure in the vapor locked area, thus condensing the vapor back into liquid, and/or
B) pumping liquid fuel around the vapor bubble, letting the engine start and flush the vapor bubble into the float chamber or the intake manifold.  This assumes the fuel plumbing permits this.
-Skip

Important component of the vapor lock is the suction. The fuel pipe does not get heated above boiling point of the fuel at normal pressure, but the suction reduces pressure, and with it reduces the boiling point. Of course it is more likely to happen if it is warm, but if the pipe is partly clogged, it will cause vapor lock at lower temperature.

As the temperature of gasoline increases, so does its vapor pressure (or vapour pressure, if you prefer).  If the vapor pressure is higher than the local absolute pressure in the fuel, then bubbles will start to form, like bubbles on the side of a glass of champagne.  Vapor lock is what happens when enough bubbles of gasoline vapor collect in a particular location to prevent a pump that is designed to pump liquid fuel, not vapor, from delivering fuel to an engine.
The problem is exacerbated by suction pumps, which reduce the absolute pressure of the fuel.  (Flow restrictions would also tend to lower the absolute pressure of the fuel locally, as @JanHudec points out.)  Vapor lock problems had been common in automobiles in hot weather, until engineers switched from suction fuel pumps to compression fuel pumps, which increase the pressure of the fuel.  Compression fuel pumps must be guaranteed a flow of fuel, which is why they are usually located inside the fuel tank in cars.  A pump inside a fuel tank is nearly universally powered by an electric motor, because a mechanical connection would be more difficult to seal against fuel leaks.
I don't know much about general aviation engines, but it sounds as though the main pump is a suction pump, which introduces the possibility of vapor lock, and I'll guess that it's mechanically-driven by the engine for reliability reasons.  I'll also guess that the electric fuel pump is a compression pump; if so, running it would increase the absolute pressure of the fuel, helping to prevent vapor lock.

Vapour outside the US lol.  Also, Z is "zed" not "zee". Anyway, boost pumps are usually suction pumps installed upstream of the EDP, typically on the firewall. On GA airplanes that's all you really need and it avoids multiple pumps installed in fuel tanks as is done on transport airplanes. The EDP on the case gets really hot from the case itself.  My plane (a homebuilt) runs on Mogas and I have had vapour lock problems in very hot weather (mostly pressure fluctuations). I installed a cooling shroud on the EDP fed with cold air from the cowl inlet and my VL problems have largely gone away.


text:
What are the speeds of the windshield wipers on an A320?
In the Airbus A320, the overhead panel wiper selector knob has three settings: Off, Slow and Fast. At what speed do the wipers operate in Slow and Fast mode?

To confirm, you are not asking about airspeed, but about the angular speed of the wiper blades themselves?  I doubt this information is published anywhere...


text:
How does pressure affect formation of clouds?
Relative Humidity is the key factor in determining cloud formation but i believe prevailing pressure system in the surrounding has to do with how fast the cloud can be formed and how long will it sustain.
Low pressure systems are generally associated with bad weather but in a fairly high pressure area (1012hPa) and high temperature (38C) and relative humidity more than 80%, why clouds cannot be formed during mid-day ?

You'll get the best answer by posting in earthscience.se, but I'll give a basic answer based on what I remember from flight school...
In general terms, cloud is formed when moist air is cooled down to its dewpoint. The main methods of cooling are through conduction (touching the cold ground or ocean) or through adiabatic cooling via convection (when the air rises and expands).
High pressure areas means the air is sinking from above. The air converges at altitude, sinks, and diverges at the surface. This limits the ability for convective cooling, making it almost impossible for daytime thunderstorms to develop.
But that doesn't mean you can't get any clouds. In fact fog, which is a cloud, basically needs high pressure in order to form, as well as a cool surface. On a hot day, the ground may be so warm that heated air 'pockets' can break through the sinking air and form cumulus clouds. Any mountain range will also force the air to rise and cool too. In the conditions you've described I wouldn't be surprised to see scattered cloud (especially as 1012hPa isn't that high). You just probably wouldn't see the large towering cumulus clouds that can develop into thunderstorms.

It depends on the amount of water vapour in the air (realative humidity).
Pressure systems within the atmosphere are large and small areas of air that contain rising (low pressure) and descending (high pressure) air; sometimes there is rising and descending air but only in very unstable conditions (thunderstorm).
In general, rising warm-moist air will create clouds as it ascends to a cooler altitude to then condesate to make 'clouds'. This rising warm-moist air is usually caused by solar radiation (convection). The rising air creates a low pressure system. Cold air in the atmosphere will descend and thus create high pressure.

why clouds cannot be formed during mid-day ?

Clouds can be formed during mid-day but they won't suddenly just appear in the sky unless the rising columns of air cool extremely fast. For example: thunderstorms can create new clouds within minutes due to the speed of the updrafts.
There may be evaporation of ground moisture and water, but the time it takes for that water to evaporate could be hindered by high pressure. However a good example of the formation of clouds during mid-day is a fire. Fires release water through combustion and create high speed rising columns of air. The air quickly rises and cools to form pyrocumulus clouds (usually).
Overall pressure does have an influence on the formation of clouds, but you as a pilot should know that low pressure systems will be related to unfavourable weather compared to high pressure systems.


text:
Is aerodynamics study compulsory for building a plane?
I want to make a plane like a trike. I have a design and some knowledge about plane requirements.

Contact the local chapter of EAA: https://www.eaa.org/eaa There are many ways to get yourself killed when you fly, especially your home-built planes - your friends in EAA will help you avoid some of them.

i think a better question is "Is aerodynamics study compulsory for building a good plane?"

What can the KSP game actually teach about spaceflight and orbital mechanics? - If it doesn't work in KSP, don't even think about it.

I would say yes. It is not mandatory to have a piece of paper, but if you don't understand the aerodynamics involved, it will be incredibly difficult to make a plane that can fly.

This question is ... incredible, yet bizarre.

You don't need to know much aerodynamics to build a plane if you follow plans for an existing design that somebody else has engineered and validated, and you don't make any modifications.
If you are trying to design and build something new, even if superficially similar to existing aircraft, then yes you will need to study aerodynamics and other aspects of aeronautical engineering. This doesn't necessarily need to be formal academic study but there is a substantial body of knowledge that you will have to learn in order for your project to be safe and successful.

Can u suggest me any book or YouTube channel name for learning aero ?

MIT OCW 16.01 to 16.04 and 16.100

A few universities offer online courses for aerospace engineering. Here's a free one from my alma mater: https://online-learning.tudelft.nl/courses/introduction-aeronautical-engineering/

@VishnuMeena - "It works in KSP."

@Mazura X-Plane would make much better sense for aicraft.

@pericynthion can u suggest me any workbook for example solution like any math or chemistry book ?

It's not compulsory as in there's no law requiring you to have studied aerodynamics in order to design an aircraft.
It is however exceedingly hard to design an efficient and safe (and able to fly at all) aircraft without a thorough understanding of aerodynamics, so studying the field is a very good idea.
What set the Wright brothers apart from many others who were trying to design and build flying machines around that time is that they went through the effort of studying and analysing other flying things, like birds, and also looked at the partially successful attempts by people like Otto Lilienthal and learned from what worked for those machines and what didn't.
Only when they had what they considered an understanding of how things worked did they set out to build their own models, gliders, and eventually powered aircraft.
Had they just set down behind their workbenches and start churning out parts to put together with little thought as to their correct shape, size, and such, they'd have failed like so many before (and since).

No, aerodynamics study is not compulsory for building an aircraft, or parts of it.
Some aircraft have been built by thousands of people, none of whom were asked for their diplomas.
But if you want to legally fly what you've build, in USA airspace, then you must choose which category it falls into and what laws apply to it.
https://www.eaa.org/eaa/aircraft-building/building-your-aircraft/getting-started/selection-articles/faa-51-rule

authors: Vladimir F Героям слава


text:
Do the speed brakes on an F-16 change its pitch?
In level flight at 400 knots, what happens when the speed brakes are extended?

I'm guessing the speed brake would rapidly depart the aircraft...

Not true. The boards will be effective at all stages of the flight. What is the reason why you said that?

I forgot they were tail mounted devices on the F-16, I was thinking of the large flap that opens on the top of some aircraft.

F15 has an "flap" on spine, it is top air brake , used for landing and in flight to slow down at any speed but it will not be fully open.

Because the speed brakes are tail mounted, and because they deploy upwards and downwards equally, pitch should not change.  The airplane's fly-by-wire system likely dampens any slight pitch changes caused by the buffeting.
The only photos I've seen of the speed brakes open are of them fully open, not partially open.  So they may open gradually with different deflections up and down, or with different resulting air loads up and down, or both, or neither.  But in any of those four cases, the FBW should correct for pitch excursions by deflecting the other control surfaces.

True, but ideally the pressure would have to be equal top /bottom. This is not the case with the body lift and chines of the F16.

How do you know that they open symmetrically @George Geo? Top and bottom part angle may be different to keep pitch moment zero.

Jpe61. The F 16 speed brakes are deployed always symmetrically up /down 60 degrees(same piston work to operate them ). Could be stopped at any angle. For landing is less because they risk to touch the ground.

No need to toss around minus points when someones asks a legitimate question @George Geo. The fact that the speedbrakes are operated by single piston/pair does not automatically mean they open symmetrically.


text:
Is there a relationship between transonic buffet magnitude and altitude?
Transonic buffet happens at mach 0.95.  The correlated true airspeed varies with altitude.  Does the transonic buffet magnitude also vary with altitude, and if so, how?

If an aircraft (fighter jet) is in transonic regime then the buffet occurs. Yes or no? But transonic  speed region's is definitely dependent on the altitudes. Yes or no? So my question: is this different altitudes gives buffet intensity( during maneuver) differently any  times? Now you understand?

I don't know about fighter jets; never flown or designed one. But for commercial aircraft, you cannot have buffet during cruise up to your maximum operating Mach number. Forbidden by regulations.

Because the real speed  is not the same. Speed of sound is less up in the thin air, and moreat lower altitudes due temperature (air density).

Recommend editing your question to the first comment. Some punctuations and explanation (for example, what motivates the question, rationale for your assumptions) would help.

Are you asking if there is a relationship between transonic buffet magnitude and altitude?

Excellent deduction, yes, due to the difference in speed ranges at the  moment when this buffet occurs.Lower the speed  of sound is higher than up  in the air

@Jpe64 "Transonic buffet happens always at mach 0.95"? That's misleading borderline incorrect.

@Jimmy that's not my statement, I merely tried to edit the question so that it would be comprehensible. You can check out the edit history to see the original question and edit further should you wish to do so.

Leave aside the correct details for the( transonic) buffet (not sure about the starting point of it) but is the buffet on the airframes always the same in intesity (slightly) ?

Mach Number Versus Airspeed (airspeed is not the same)

Transonic buffet, or Mach induced buffet, or high speed buffet, is a flow separation due to the combined presence of shockwave and "high" angle of attack. The boundary layer separation results in random high frequency vibrations. As the AOA increases, the separation and the associated vibrations worsen, up to the point where the crew can no longer read the instrumentation and perform normal flight duties; this point is called deterrent buffet.
For a single Mach number, the AOA (or $C_{L}$) associated with buffet onset is generally constant; there will be some differences due to CG position, the associated trim and Reynolds number effects. During aircraft design and flight testing, the buffet onset boundary similar to the one below is mapped out. As you can see, the general trend is a decrease in buffet onset boundary with Mach (though the trend can reverse depending on the airplane).

(Image modified from https://www.researchgate.net/figure/Typical-buffet-onset-curve-and-separation-mechanisms-defining-the-boundaries_fig2_270086469.)
Flying at the same Mach number at a higher altitude means that it will have smaller dynamic pressure than flying at a lower altitude. This translates to a higher AOA at the higher altitude, which means that the buffet intensity will be higher. In other words, for the same Mach and weight, the maneuver margin is decreased the higher it flies, independent of its climb capability.

Thanks "This translates to a higher AOA at the higher altitude, which means that the buffet intensity will be higher" is the answer to the question. Because of the AOA at higher altitudes the buffet is more aggressive than the lower altitudes.


text:
Calculating lift with lifting-line theory in MATLAB
I am attempting to calculate the lift generated by a model wing (~0.8$m^2$ wing area) using Prandtl's lifting-line theory in MATLAB. I am starting with the equation below from Anderson's 2005 book Fundamentals of Aerodynamics:

I have defined the $\frac{2b}{\pi c(\theta)}$ as '$\mu$' for simplicity, moved this back into the first summation and rearranged the above to:
$\Sigma A_n\sin(n\theta)(\mu + \frac{n}{sin(\theta)}) = \alpha(\theta) - \alpha_0(\theta)$
Presumably if I split the half-wing section (i.e from $\theta = \pi/2$ to $\pi$) into 10 segments I can generate a set of simultaneous equations from $n = 1$ to $10$ and $\theta_1$ to $\theta_{10}$. Solving that set of equations should then give me values of $A_1$ through to $A_{10}$. However, the values I'm generating for my coefficient matrix, $B$, (i.e. the $\sin(n\theta)(\mu...)$ bit) seem to be off, reaching 65 for $\theta_1$ and $n =10$. This is turn gives me incorrect values of the $A$ coefficients. Both are shown below:

This leads me to believe something must be off in either my re-arrangement above or my MATLAB code, which is shown below for completeness. It might be inefficient but please ignore that for now! Anyone able to assist with where I might be going wrong? Would be greatly appreciated!
MATLAB Code:
clear all
clc

% Wing segments:
N_seg = 10;
N_seg2 = N_seg;

% Flow:
U_0 = 15.433 % [m/s]
sweep = deg2rad(30); % Sweep angle
U_n = U_0 * cos(sweep); % Flow component travelling normal to wing sweep

% AoA and zero-lift AoA:
AoA = 0;
AoA_0 = -6.4;

% Wing twist, to be confirmed following further design:
twist = 0;

% Initiliase segment chord, theta and AoA matrix:
c = zeros(1,N_seg);
theta = zeros(1,N_seg);
AoA_seg = zeros(1,N_seg);

% Lambda range:
for Lambda = 0.25:0.25:0.5

% Wing area, span, chord etc.
S = 0.8; % [m^2], wing area
b = 1.56827; % Wing span
s = b/2; % Semi-wing span
c_root = (2*S) / ((1 + Lambda) * b); % root chord [m]

c(1) = c_root; % setting root chord as inner segment wing chord
theta(1) = pi/2;
AoA_seg(1) = AoA;

% tip chord [m]
c_tip = ((2*S) / ((1 + Lambda) * b)) * (1 - ((2* (1 - Lambda)) / b) * (b/2) );
% mean aerodynamic chord [m]
MAC = (2/3) * (c_root + c_tip - (c_root * c_tip) / (c_root + c_tip))

    % Segment chord lengths and theta to wing tip:
    for N_seg = 2:N_seg
        % Chord length of each segment, linear interpolation
        c(N_seg) = c_root + (c_tip - c_root)/N_seg2 .* N_seg
        % Theta of each segment;- first segment must not be 0,
        % otherwise singular matrix obtained
        theta = pi/(2*N_seg):pi/(2*N_seg):pi/2;

        % AoA of each segment , linear interpolation
        AoA_seg(N_seg) = AoA + (twist)/N_seg2 .* N_seg
    end
    mu = 2*b./(pi*c);

    % Setting up RHS (B) and LHS matrix:
    for i = 1:N_seg
        for j = 1:N_seg
            B(i,j) = (sin(j .* theta(i))) .* (mu(i) + j/(sin(theta(i))))
        end
    LHS(i) = (AoA_seg(i) - AoA_0) * (pi/180);
    end

    % Finding A coefficients:

    A = B\transpose(LHS)

end

If you suspect a problem in your MatLab code you might do well to post that part of this question on [so]

Your general formulation seems fine. Two things to point out:

If you choose to sample only half the wing, then you cannot utilize the relation: $C_L=A_1\pi A$. You would have to do the integration: $C_L=\frac{2}{V_\infty S}\int^{b/2}_{-b/2}{\Gamma(y)dy}$. That being said, maybe you can simplify the expression and get a closed-form result? Haven't tried myself.
Your code doesn't seem to handle for the case where $\sin(\theta)=0$.

You can take a look at the code below for reference:
% Wing area, span, chord etc.
S = 0.8; % [m^2], wing area
b = 1.56827; % Wing span
s = b/2; % Semi-wing span
taper = 0.25;
Cr = S/s/(1+taper);
Ct = taper*Cr;
MAC = 2/3*Cr*(1+taper+taper^2)/(1+taper);
AR = b^2/S;

% AoA and zero-lift AoA:
AoA = deg2rad(0);
AoA_0 = deg2rad(-6.4);

% Discretization
num = 10;
[N,Ts] = meshgrid(1:num, linspace(0,pi,num));
ys = -s*cos(Ts);
Cs = (Ct-Cr)/s*abs(ys)+Cr;

% Construct linear system
B = 2*b/pi./Cs.*sin(N.*Ts)+N.*sin(N.*Ts)./sin(Ts);
if Ts(1)==0
    % Singular case, use l'Hopital's rule
    B(1,:) = N(1,:).*N(1,:);
end
RHS = AoA - ones(num,1)*AoA_0;

% Solve
A = B\RHS;
CL = A(1)*pi*AR;